Epitaxial growth of vanadyl-phthalocyanine ultrathin films on hydrogen-terminated Si(111) surfaces

Abstract

Ultrathin films of vanadyl phthalocyanine (VOPc) have been grown on hydrogen-terminated Si(111) surfaces by molecular beam epitaxy. Epitaxial growth was examined on the two types of substrates. Reflection high energy electron diffraction studies have revealed that VOPc molecules form commensurate lattices [−3[3 1]4], [−1[4 3]3], and [1[4 4]1] on the surface terminated homogeneously with monohydride. On the other hand, epitaxial growth did not occur on the surface terminated with the mixture of polyhydride. Homogeneity and microscopic flatness of the substrate surface seem to be important factors for the epitaxial growth of VOPc on the hydrogen-terminated Si substrate.